RIASSUNTO
The paper studies families of positive solution curves for non-autonomous two-point problems [ u"+lambda f(u)-mu g(x)=0, ;; -1<x<1, ;; u(-1)=u(1)=0 ] depending on two positive parameters $lambda$ and $mu$. We regard $lambda$ as a primary parameter, giving us the solution curves, while the secondary parameter $mu$ allows for evolution of these curves. We give conditions under which the solution curves do not intersect, and the maximum value of solutions provides a global parameter. Our primary application is to constant yield harvesting for diffusive logistic equation. We implement numerical computations of the solution curves, using continuation in a global parameter, a technique that we developed in [11].
Comment: 17 pages, 4 figures